The present invention relates to a direct injection internal combustion engine of a center injection type in which a fuel injection valve and a spark plug are disposed at a middle part of an upper part of a combustion chamber.
In a spark ignition combustion, fuel is injected directly from a fuel injection valve into a cylinder to form a stratified air-fuel mixture in the cylinder. An internal combustion engine thereby performs a wide-ranging lean burn or combustion. Such internal combustion engine can largely reduce a fuel consumption especially in a low/intermediate-load combustion.
Japanese Patent Application Publication No. H11(1999)-22592 discloses a direct injection internal combustion engine of a center injection type in which a fuel injection valve is disposed at a middle part of an upper part of a combustion chamber, and a spark plug is directed toward a central part of the combustion chamber. In such direct gasoline-injection engine, fuel is injected from the middle part of the upper part of the combustion chamber toward the central part of the combustion chamber to form a stratified air-fuel mixture in a wide-ranging area. Such direct gasoline-injection engine thereby can perform a stratified charge combustion in a wide region of operating range.